So What Happens If We Were To Fall Into A Black Hole?

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ALPiNe
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So What Happens If We Were To Fall Into A Black Hole?

Post by ALPiNe »

So What Happens If We Were To Fall Into A Black Hole?

Have you ever wondered what it would be like traveling through space in a spaceship when suddenly, out of nowhere, you felt a sudden sharp jerk and the next thing you knew, you have fallen into a black hole? “If so, then you are already aware of how attractive the notion of being devoured by a black hole is for human imagination. What you may not know is that this notion also is attractive to astrophysicists. In fact, the theoretical models of what happens inside the event horizon seem to move in and out of accepted physics theory rather rapidly.

All of these theories share a common feature- the black holes arose because of the gravitational effects of a mass on space. Different theories assign different sorts of the gravitational effects on space, and therefore predict black holes with different properties. In general, however, they share a common notion: the possibility of an inevitable terror lurking invisibly in space, warping both space and time.” (Adapted from James Trefil, The Edge of the Unknown).

According to James Trefil in The Edge of the Unknown, “There are a number of ways to picture black holes. The simplest way is as masses crammed into so tiny a space, exerting so strong a gravitational force, such that if you shone a flashlight up from the surface, the light could never escape. Or you could also be a little more abstract and say that mass is so concentrated such that it wraps space around it like a blanket. Anyway you picture a black hole though, you get a place cut off from the universe. Any light falling on it will never come out, which means that it will appear black (hence its name).”

Now, in your classic black hole, all matter eventually contracts to a single point called a “singularity”, where density and pressure are infinite and space and time are of no importance. Here, their temperature hovers at -273°C. If you were to dive into a black hole, the first thing to realize after passing “through the event horizon in finite proper time (that is, time as measured by your watch, or by your internal sense of time)”, would be the sudden vanishing of the frozen star as you are about to strike it-of which I would explain in the later part. You will then be cruelly driven into its centre after a certain amount of your time has elapsed, no matter how much, or how hard you try to escape from being crushed out of existence into a point at the singularity (Black Holes-Clifford A.Pickover).

On the other hand, according to Erik Max Francis-a freelance science writer, “from the point of view of an observer very far from the black hole-that is, outside the black hole’s gravitational influence, also known as ‘asymptotically flat space-time’-the observer would watch you fall towards the black hole and then begin to slow as you approached the event horizon”-due to time dilation. “In fact, from his point of view, you would never even reach the horizon, and very quickly, your image would be redshifted and dimmed so that you could no longer be detectable.”

To account for this apparent contradiction, what the distant observer perceives is your image, not you. Since “all images are carried by light, therefore, a remote observer detects you by the light coming or being reflected from you.” A black hole is believed to distort spacetime in such a way that space-time is flowing into the black hole. Soon, you will realise why the event horizon is a point of no return in this model-“Abandon Hope, All Ye Who Enter.” Simply put, “the event horizon is the radius around a black hole where ‘space-time is flowing inward at the speed of light.’ Since nothing can travel faster than light at the event horizon, this means that nothing can ever escape” from the clutches of the strong gravitational field of the black hole, once it has fallen within the event horizon.

Using this similar concept, we can then explain what is happening with your image as you approach a black hole. Take this instance “where you are falling into a black hole while emitting light through a torchlight. As you get closer and closer to the event horizon, the light which you are emitting, or reflecting to an outside observer, is taking longer and longer to get out of the black hole. Since light moves at exactly c, and the closer you get to the horizon the faster space-time is ‘flowing inward,’ the relative propagation of light out of the black hole is slower. At the event horizon itself, any photon emitted out of the black hole will just stay there, since it’s moving at c, but space-time is ‘flowing inward’ at c.” The end result gives rise to an image, your image, which “appears to forever hover just outside the horizon, even though you have long since fallen in and met your doom at the singularity.” In a similar way, the vanishing of the frozen star mentioned earlier on is due to the light it had emitted as it collapsed through its own horizon which is still leaking out and making it look as though it were still there.

Apart from these, there are a few other widely accepted possibilities of what to expect if we did go inside the event horizon of a black hole, of which I would only touch on very briefly.

Theoretical physicists speculated that for one to fall in a non-rotating electrically neutral black hole, the unfortunate will ultimately meet his impending doom at the point of singularity. As for an average rotating black hole, with or without electrical charge, one would die quite horribly-being stretched on both ends mercilessly due to tidal forces, even before he gets to the event horizon, as was so for the non-rotating case. “Another possibility is that the black hole would warp the space-time continuum in such a way that something called a ‘wormhole’ or an ‘Einstein-Rosten bridge' would be formed.” You would be sucked into this wormhole out into another dimension, of which no one will ever know about (Cecil Adams, The Straight Dope).

With no disrespect for theories about the interior of a black hole, I would love to adopt a theory put forth by an unknown author, who named it the "Pink Hippo" theory. This theory suggests that as matter passes the event horizon, it is transformed into pink hippos wearing tutus and toe shoes that dance their way to the center in an endless ballet. However ludicrous this sounds, no one will ever be able to disprove it, unless they go into a black hole and then of course, they will never make it back to tell their story. If someone were to bet on this, then the only way to settle the bet would be for both parties to dive into a black hole together!

“The reason that the notion of what goes on in the black hole seems to go in and out of fashion is that astrophysicists are limited to the theoretical models.” Obviously, even if they could study a nearby black hole (“scientists have already accumulated evidence of large black holes in some galaxies, including our own Milky Way”), they would never be able to find out what happened to a probe that went inside. But one thing is for sure: Death, possibly, for the future generations to come should the existence of black holes be affirmed "in this strange universe we inhibit.” (Adapted from James Trefil, The Edge of the Unknown).


- ALPiNe :)



Websites (Images):

Galactic Black holes
http://www.space.com/php/multimedia/ima ... ack%20hole.

http://www.space.com/php/multimedia/ima ... ack%20hole.

Black Holes
http://hubblesite.org/newscenter/newsde ... s/2002/18/
http://hubblesite.org/newscenter/newsde ... s/1997/28/
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